Question

2. copper(ii) nitrate trihydrate was found to contain 37.5 g of anhydrous salt. what was the mass of the initial hydrated compound subjected to the same gravimetric method used in this lab?

Answer 1

To find the mass of the initial hydrated copper(II) nitrate trihydrate, calculate the moles of anhydrous copper(II) nitrate from the given mass and then multiply by the molar mass of the hydrated form.

Step-by-step explanation:

The question asks to determine the mass of the initial hydrated copper(II) nitrate trihydrate compound from the mass of the anhydrous salt that was obtained through a gravimetric method. To solve this problem, we will consider the molecular mass of both the hydrated and anhydrous forms of copper(II) nitrate.

The formula for copper(II) nitrate trihydrate is Cu(NO3)2 · 3H2O and for anhydrous copper(II) nitrate, it's Cu(NO3)2. We'll use the mass of the anhydrous salt given (37.5 g) to calculate the moles of copper(II) nitrate, and then use the mole ratio to determine the mass of the hydrated compound.

First, calculate the molar mass of anhydrous copper(II) nitrate (Cu(NO3)2), which is the sum of the atomic masses of copper (Cu), nitrogen (N), and oxygen (O) in the formula. Then, calculate the molar mass of copper(II) nitrate trihydrate (Cu(NO3)2 3H2O). The mass of the hydrated compound is determined by multiplying the moles of the anhydrous compound by the molar mass of the hydrated compound.

Answer 2

To find the mass of the initial hydrated copper(II) nitrate compound, we can calculate the molar mass of the anhydrous salt and use stoichiometry to find the mass of the initial hydrate. The mass of the initial hydrated compound is approximately 49.36 g.

Step-by-step explanation:

To find the mass of the initial hydrated copper(II) nitrate compound, we need to calculate the molar mass of the anhydrous salt and use stoichiometry to find the mass of the initial hydrate. The molar mass of copper(II) nitrate (Cu(NO3)2) is 183.53 g/mol. Since the anhydrous salt (Cu(NO3)2) has a mass of 37.5 g, we can set up the following equation to find the mass of the initial hydrated compound:

37.5 g (anhydrous salt) / 183.53 g/mol (molar mass of anhydrous salt) = x g (initial hydrated compound) / 241.59 g/mol (molar mass of hydrated compound)

Solving for x, we find that the mass of the initial hydrated compound is approximately 49.36 g.